I've got a question, I thought perhaps one of you fine human beings could help me out.

I am under the impression that you can find the relative minor key of a major key by counting down 3 steps, alternately, you can find the relative Major by counting up 3 steps from the minor. That minor should have the same amount of sharps and flats as it's relative Major. Correct so far?

So, I'm doing an exercise that requires me to identify the diatonic 7th chord for a particular scale degree of a particular minor key. The question is in the form of; B Minor, VII7 = _ _ _ _ _ . So for that instance, I got A7.
I worked that out by first identifying the relative major of B, which is D, which I know has 2 sharps, F and C. Then I wrote out the B Minor scale and knew that A was the 7th degree, and that the 7th degree of a minor diatonic progression would make it a Dominant 7th, thus A7.

Now, when I go to the next example; F Minor, v7 = _ _ _ _, I try to repeat the same process but it doesn't work. A 3rd up from F is A, A Major has 3 sharps, so F C G are sharp, but F Minor obviously can't have an F# in it. So what am I missing? I know I can just write out F minor by the W-H-W-W-H-W formula, but I'm trying to do it with the relative major/minor formula. Halp?

3 Answers
3

F minor has 4 flats (Bb, Eb, Ab, Db) its relative major would be Ab Major. Knowing that the v7 for F minor is a C minor 7th (C, Eb, G, Bb) as per the f minor scale but if we are in the context of the F harmonic minor then this chord would be C, E, G, Bb. Context matters here.
(corrections made.)

I think this is a kind of round about way at learning relative chords. Better to learn your key signatures by heart as a more direct route to the answer. Thinking about the relative major and minor has its place but this does not appear to be here.

This may sound annoying and hard to you, but to avoid this type of problem you could try memorizing which keys have which sharps and flats so you don't have to rely on counting half steps. This way you can quickly think "E♭ major has three flats, c minor has three flats..." without counting the half-steps.